TETRAHEDRAL GEOMETRY/TOPOLOGY SEMINAR

         ANNOUNCEMENT

DATE:              Friday, March 30, 2007                

LOCATION:    Hempfield High School, Room 213 (directions at http://www.millersville.edu/~tgts/)                

                           followed by dinner at a place to be determined.

4:30 TALK:      Andrew Hicks, Drexel University

                           “Direct Methods of Optical Design”

                           The first photograph was created in 1827 by Joseph Nicephore Niepce.  In 1828,

                           William Rowan Hamilton's founding papers on geometric optics began to appear.

                           This seems to be a remarkable coincidence and one would think that the two siblings,

                           photography and geometric optics, would each contribute to the growth of the other.

                           But this never happened. Optical design in the 19th century was largely empirical,

                           and today design in the geometric realm is often performed by optimizing a cost

                           function which is defined via ray tracing. For example, Hamilton's name appears

                           nowhere in Rudolf Kinglslake's  book "A History of the Photographic Lens."

                           Recent advances in machining, such as 5-axis diamond turning, have now made it

                           possible to make high quality freeform optical surfaces, i.e. surfaces that do not have

                           rotational symmetry. This opens up a whole new realm of design possibilities for

                           illumination and imaging applications, but little theory exists for the design of such

                           surfaces. I will describe methods that I have developed for this problem, based on

                           differential geometry and partial differential equations. For some optical design

                           problems, the surfaces may be modeled as integrals of distributions in Euclidean

                           space. Hints of connections between Hamiltonian optics and these methods appear,

                           but the full story remains unclear. Applications include the design of wide-angle and

                           panoramic imaging systems, and side view mirrors for motor vehicles without blind spots.

     EVERYONE WELCOME

       PLEASE FORWARD THIS ANNOUNCEMENT TO ANYONE INTERESTED

           The Tetrahedral Geometry/Topology Seminar is sponsored jointly by

Elizabethtown College, Franklin & Marshall College, Lebanon Valley College and Millersville University.